Jean, Beast, Colossus, Kitty, Pyro, Iceman, Rogue and Jubilee have been in 3.

Banshee, Emma Frost, Moira, Siryn and Stryker Jr. have been in 2.

*Cyclops may have been in 5 if you consider the young boy in the Cerebro scene in FC who's sporting Scott's colors and a pair of dark shades.
**Storm would have been in 5 had her cameo in XO:W not been cut.

So far, we know certain numbers (only for confirmed characters) will change after TW and DoFP come out: